A vehicle, such as an automobile, includes a frame and an underbody supported by the frame. The vehicle typically includes a subframe for supporting various components of an engine, drivetrain, and/or suspension of the vehicle. The subframe is typically mounted to the underbody of the vehicle with bolts, welding, etc. The subframe extends forwardly from the underbody toward a front bumper of the vehicle.
During frontal impacts of the vehicle, such as those defined by Federal Motor Vehicle Safety Standards (FMVSS) and Insurance Institute for Highway Safety (IIHS) standards, front structural components of the vehicle deform to absorb energy. Subframes of some vehicles are not designed to detach from the underbody. Such designs typically require additional energy absorbing features and restraint systems to properly handle energy during a frontal impact.
Other subframes are designed to detach from the underbody during frontal impact to change the pulse and Vehicle Pulse Index during the frontal impact. Detachable subframes can be designed to shear the connection between the subframe and the underbody; however, this shearing can create design difficulties. There remains an opportunity to design a subframe that effectively detaches from the underbody during frontal impact.